Nitrous with SPS 62 thoughts

C

ctd2001

New member
I have purchased a single stage kit for the reason that it was brand new and less then half of retail. Nitrous was never in my build plans but for the cost of the kit I thought I might try it. I am wondering if the wastegate on the SPS 62 is sufficient enough to keep my drive pressure tolerable or if I should add a external gate. The exhaust manifold has wastegate port machine into it already with just a block off plate covering the port. The biggest jet that the kit came with is a .055 which the kits says is roughly a 130hp increase. From what I have been reading that seems like a rather small jet. I only plan on using the nitrous on occasional weekend trips to the track.
Also, as far as setting up the nitrous, I plan to run a zex programmable tps switch which will only activate the system at WOT. I'm going to wire it with a HOBBs switch set around 25psi boost, so the system wont spray until WOT and 25lbs boost. Also acts as a safety incase the Hobbs fails, the system will deactivate when no longer at WOT. Mods are, studs, 7x12 injectors, edge ez, tst comp, SPS 62, Scheid cam, 110 springs, push rods and FASS. Thanks for the input
 
Should do okay with the internal gate and a .055 jet. I ran a .073 solenoid and a hogged out pill and my gate was coming open around 50psi and holding it to 57 max. My turbo is a 66, but the waste gate pucks should be the same.

Sounds like you did your research and you have a plan. Good job!
 
I wouldnt worry about the WOT switch. What happens if you are really loading it up on fuel and accidently get anxious with the pedal and stab it? BOOM, backfire.. Or if your out on a back road showing one of your friends and go to step on it before the turbos lit? Just get a N/O Hobbs switch and wire it up for that like you mentioned. THat way its off till you built up enought psi to close it and complete the circut. Then when its under the psi range it will open and be disengauged. Even if it the switch goes bed, you can just wire the two wires together and just use the toggle switch to activate it until you get a new one.

Thats how i had mine set up. I had a sps 66 with many different size injectors and played around with the smallest nozzel to no nozzel in the nitrous line. I had my hobbs set at 17-19 psi. Thats where my turbo was pulling hard at. When my nitrous injected i could gain right at 200hp in a snap. But when the turbo finished lighting it would plain out and only gain me about 40hp.

Your setup will be a little different since you have a pretty small turbo and a good bit of fuel. I would start out with a small 35-45 pill first. See where your turbo lights and then adjust the hobbs down from there. It should be adjustable with an allen screw in the back. I believe there is a rubber plug that you can take out to get to it.
 
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Thanks for the reply, I think I will install a drive pressure gauge as well just to try to monitor what's happening. Got to figure out where to mount that and the nitrous pressure gauge now, I'm running out of room quick in the cab lol
 
Firemed, I want to install it with a WOT switch for a couple of reason, first is a safety precaution if to the Hobbs switch ever failed and never turned off, it won't continue to spray because the truck won't be at WOT anymore. So in order for my system to spray, it will need to be first armed, then it will have to be at WOT and at what ever boost my HOBBS switch is set at. So as long as my system is not armed, I can be at WOT as much as I like and not worry about it spraying.
I'm going to do like you said and start with the smaller pills and work my way up, never played with this stuff before so it will be a learning experience.
 
You will be fine with the internal gate with nitrous, just may have to adjust the wastegate in order to keep the boost and drive pressure under control. A few years ago I ran an SPS 62 on a 24 valve with a similar setup and two 100 jets and made right at 700hp to the wheels.
 
Rockjeep73, how did you have your setup, where you running a progressive controller or WOT switches and HOBBS switches? When did you have your nitrous start spraying? Thanks
 
Did the same with a SPS 66, ran the 02 on a hobbs switch opening up at 20 psi. system was originally a -4 line .063 solenoid with bottom discharge and no jet..... designed that way, mounted it in the per intercooler pipe (and you should too) made 600 on fuel and 800 on the bottle.

Jim
 
I was running a progressive controller activated through full throttle. Would start spraying about 15psi.
 
ctd2001 said:
Rockjeep73, how did you have your setup, where you running a progressive controller or WOT switches and HOBBS switches? When did you have your nitrous start spraying? Thanks
Click to expand...

I would not bother with a progressive controller until are adding enough jet that you think you will actually want to use the nitrous controller for power management.

On the smaller jets and solenoids, you have enough adjustability with the hobb switch to get everything to work just fine.

Save the 300$ until you are sure you want to keep using the nitrous and then are at a point where you are spraying a larger amount.
 
That was my thought to with the progressive controller even though it is a nice unit, but the cost of the unit I couldn't justify with just spraying a single shot, maybe later on down the road
 
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